1. Field of the Invention
The present invention relates to devices designed to separate clear stock from fats, oils, and meat solids derived from cooking meat or fowl.
2. Description of the Prior Art
Prior art separating systems generally do not use a screen filter to separate out small particles of meat from the stock. Where a screen filter is applied, it is often inconvenient to use. For example in U.S. Pat. No. 4,934,420 the screen is simply placed over the top of the collection vessel. The edge of the screen filter has nothing to prevent particles of meat from falling over the edge of the collection vessel and on to the counter below.
U.S. Pat. No. 5,297,476 also uses a screen filter with only a slight depression for holding the meat particles from pouring over the side. Although the depression is an improvement over the flat screen filter of U.S. Pat. No. 4,934,420 described above, it is not enough to assure that larger sections of meat will not fall over the sides when poured into the filter.
Another problem area found in prior an separators often involves the flow valve used to control the flow of liquid from the collection vessel. The valve is often difficult to operate and difficult to clean. For example, in U.S. Pat. No. 3,713,788 the control rod for the valve extends up through the stock and fat layer. The control rod is an extra component which must be cleaned because of its position in the stock and fat. Actuation of the control rod requires the operator's hand to be on top of the separator while the operators head must be to the side to see where the fat layer is located.
Yet another problem area with prior art separators is controlling the point at which the flow valve is shut off to prevent fat from being added to the clear stock as it is drained from the collection vessel. This is due to a funnel-like collection vessel used in many prior art devices such as those shown in U.S. Pat. Nos. 3,865,023, 4,331,189, 4,389,926, 4,460,185, 4,464,265, 4,934,420, and 5,297,476. In these inventions, the rate at which the liquid drops in the collection vessel is relatively slow when the liquid is in the wide upper area of the collection vessel. However, as the fluid drops in the collection vessel, the rate at which it drops increases because of the smaller cross section of the collection vessel at lower levels. Finally when the fluid is near the neck at the bottom of the vessel, the rate of drop can be ten times as fast as when the fluid was near the top of the vessel. It becomes especially difficult to control the valve at such times because it must be shut off quickly to prevent fat from mixing with the clear stock When there is only a small mount of stock initially available, this problem is important because all the stock resides in the lower levels of the funnel-like collection vessel and the rate of drop of the fluid in the collection vessel starts out fast and gets faster, making accurate control of the flow valve extremely difficult.
The needed improvements in separators pointed out in the above discussion of the prior art have been incorporated in the present invention, and are described m the following specifications.